//  json2.js
//  2017-06-12
//  Public Domain.
//  NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.

//  USE YOUR OWN COPY. IT IS EXTREMELY UNWISE TO LOAD CODE FROM SERVERS YOU DO
//  NOT CONTROL.

//  This file creates a global JSON object containing two methods: stringify
//  and parse. This file provides the ES5 JSON capability to ES3 systems.
//  If a project might run on IE8 or earlier, then this file should be included.
//  This file does nothing on ES5 systems.

//      JSON.stringify(value, replacer, space)
//          value       any JavaScript value, usually an object or array.
//          replacer    an optional parameter that determines how object
//                      values are stringified for objects. It can be a
//                      function or an array of strings.
//          space       an optional parameter that specifies the indentation
//                      of nested structures. If it is omitted, the text will
//                      be packed without extra whitespace. If it is a number,
//                      it will specify the number of spaces to indent at each
//                      level. If it is a string (such as "\t" or "&nbsp;"),
//                      it contains the characters used to indent at each level.
//          This method produces a JSON text from a JavaScript value.
//          When an object value is found, if the object contains a toJSON
//          method, its toJSON method will be called and the result will be
//          stringified. A toJSON method does not serialize: it returns the
//          value represented by the name/value pair that should be serialized,
//          or undefined if nothing should be serialized. The toJSON method
//          will be passed the key associated with the value, and this will be
//          bound to the value.

//          For example, this would serialize Dates as ISO strings.

//              Date.prototype.toJSON = function (key) {
//                  function f(n) {
//                      // Format integers to have at least two digits.
//                      return (n < 10)
//                          ? "0" + n
//                          : n;
//                  }
//                  return this.getUTCFullYear()   + "-" +
//                       f(this.getUTCMonth() + 1) + "-" +
//                       f(this.getUTCDate())      + "T" +
//                       f(this.getUTCHours())     + ":" +
//                       f(this.getUTCMinutes())   + ":" +
//                       f(this.getUTCSeconds())   + "Z";
//              };

//          You can provide an optional replacer method. It will be passed the
//          key and value of each member, with this bound to the containing
//          object. The value that is returned from your method will be
//          serialized. If your method returns undefined, then the member will
//          be excluded from the serialization.

//          If the replacer parameter is an array of strings, then it will be
//          used to select the members to be serialized. It filters the results
//          such that only members with keys listed in the replacer array are
//          stringified.

//          Values that do not have JSON representations, such as undefined or
//          functions, will not be serialized. Such values in objects will be
//          dropped; in arrays they will be replaced with null. You can use
//          a replacer function to replace those with JSON values.

//          JSON.stringify(undefined) returns undefined.

//          The optional space parameter produces a stringification of the
//          value that is filled with line breaks and indentation to make it
//          easier to read.

//          If the space parameter is a non-empty string, then that string will
//          be used for indentation. If the space parameter is a number, then
//          the indentation will be that many spaces.

//          Example:

//          text = JSON.stringify(["e", {pluribus: "unum"}]);
//          // text is '["e",{"pluribus":"unum"}]'

//          text = JSON.stringify(["e", {pluribus: "unum"}], null, "\t");
//          // text is '[\n\t"e",\n\t{\n\t\t"pluribus": "unum"\n\t}\n]'

//          text = JSON.stringify([new Date()], function (key, value) {
//              return this[key] instanceof Date
//                  ? "Date(" + this[key] + ")"
//                  : value;
//          });
//          // text is '["Date(---current time---)"]'

//      JSON.parse(text, reviver)
//          This method parses a JSON text to produce an object or array.
//          It can throw a SyntaxError exception.

//          The optional reviver parameter is a function that can filter and
//          transform the results. It receives each of the keys and values,
//          and its return value is used instead of the original value.
//          If it returns what it received, then the structure is not modified.
//          If it returns undefined then the member is deleted.

//          Example:

//          // Parse the text. Values that look like ISO date strings will
//          // be converted to Date objects.

//          myData = JSON.parse(text, function (key, value) {
//              var a;
//              if (typeof value === "string") {
//                  a =
//   /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2}(?:\.\d*)?)Z$/.exec(value);
//                  if (a) {
//                      return new Date(Date.UTC(
//                         +a[1], +a[2] - 1, +a[3], +a[4], +a[5], +a[6]
//                      ));
//                  }
//                  return value;
//              }
//          });

//          myData = JSON.parse(
//              "[\"Date(09/09/2001)\"]",
//              function (key, value) {
//                  var d;
//                  if (
//                      typeof value === "string"
//                      && value.slice(0, 5) === "Date("
//                      && value.slice(-1) === ")"
//                  ) {
//                      d = new Date(value.slice(5, -1));
//                      if (d) {
//                          return d;
//                      }
//                  }
//                  return value;
//              }
//          );

//  This is a reference implementation. You are free to copy, modify, or
//  redistribute.

/*jslint
    eval, for, this
*/

/*property
    JSON, apply, call, charCodeAt, getUTCDate, getUTCFullYear, getUTCHours,
    getUTCMinutes, getUTCMonth, getUTCSeconds, hasOwnProperty, join,
    lastIndex, length, parse, prototype, push, replace, slice, stringify,
    test, toJSON, toString, valueOf
*/

// Create a JSON object only if one does not already exist. We create the
// methods in a closure to avoid creating global variables.

var rx_escapable =
	/[\\"\u0000-\u001f\u007f-\u009f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g;

function f(n) {
	// Format integers to have at least two digits.
	return n < 10 ? "0" + n : n;
}

function this_value() {
	return this.valueOf();
}

if (typeof Date.prototype.toJSON !== "function") {
	Date.prototype.toJSON = function () {
		return isFinite(this.valueOf())
			? this.getUTCFullYear() +
					"-" +
					f(this.getUTCMonth() + 1) +
					"-" +
					f(this.getUTCDate()) +
					"T" +
					f(this.getUTCHours()) +
					":" +
					f(this.getUTCMinutes()) +
					":" +
					f(this.getUTCSeconds()) +
					"Z"
			: null;
	};

	Boolean.prototype.toJSON = this_value;
	Number.prototype.toJSON = this_value;
	String.prototype.toJSON = this_value;
}

var gap;
var indent;
var meta;
var rep;

function quote(string) {
	// If the string contains no control characters, no quote characters, and no
	// backslash characters, then we can safely slap some quotes around it.
	// Otherwise we must also replace the offending characters with safe escape
	// sequences.

	rx_escapable.lastIndex = 0;
	return rx_escapable.test(string)
		? '"' +
				string.replace(rx_escapable, function (a) {
					var c = meta[a];
					return typeof c === "string"
						? c
						: "\\u" + ("0000" + a.charCodeAt(0).toString(16)).slice(-4);
				}) +
				'"'
		: '"' + string + '"';
}

function str(key, holder) {
	// Produce a string from holder[key].

	var i; // The loop counter.
	var k; // The member key.
	var v; // The member value.
	var length;
	var mind = gap;
	var partial;
	var value = holder[key];

	// If the value has a toJSON method, call it to obtain a replacement value.

	if (value && typeof value === "object" && typeof value.toJSON === "function") {
		value = value.toJSON(key);
	}

	// If we were called with a replacer function, then call the replacer to
	// obtain a replacement value.

	if (typeof rep === "function") {
		value = rep.call(holder, key, value);
	}

	// What happens next depends on the value's type.

	switch (typeof value) {
		case "string":
			return quote(value);

		case "number":
			// JSON numbers must be finite. Encode non-finite numbers as null.

			return isFinite(value) ? String(value) : "null";

		case "boolean":
		case "null":
			// If the value is a boolean or null, convert it to a string. Note:
			// typeof null does not produce "null". The case is included here in
			// the remote chance that this gets fixed someday.

			return String(value);

		// If the type is "object", we might be dealing with an object or an array or
		// null.

		case "object":
			// Due to a specification blunder in ECMAScript, typeof null is "object",
			// so watch out for that case.

			if (!value) {
				return "null";
			}

			// Make an array to hold the partial results of stringifying this object value.

			gap += indent;
			partial = [];

			// Is the value an array?

			if (Object.prototype.toString.apply(value) === "[object Array]") {
				// The value is an array. Stringify every element. Use null as a placeholder
				// for non-JSON values.

				length = value.length;
				for (i = 0; i < length; i += 1) {
					partial[i] = str(i, value) || "null";
				}

				// Join all of the elements together, separated with commas, and wrap them in
				// brackets.

				v =
					partial.length === 0
						? "[]"
						: gap
							? "[\n" + gap + partial.join(",\n" + gap) + "\n" + mind + "]"
							: "[" + partial.join(",") + "]";
				gap = mind;
				return v;
			}

			if (value._$isNumber) {
				return value.toString();
			}

			// If the replacer is an array, use it to select the members to be stringified.

			if (rep && typeof rep === "object") {
				length = rep.length;
				for (i = 0; i < length; i += 1) {
					if (typeof rep[i] === "string") {
						k = rep[i];
						v = str(k, value);
						if (v) {
							partial.push(quote(k) + (gap ? ": " : ":") + v);
						}
					}
				}
			} else {
				// Otherwise, iterate through all of the keys in the object.

				for (k in value) {
					if (Object.prototype.hasOwnProperty.call(value, k)) {
						v = str(k, value);
						if (v) {
							partial.push(quote(k) + (gap ? ": " : ":") + v);
						}
					}
				}
			}

			// Join all of the member texts together, separated with commas,
			// and wrap them in braces.

			v =
				partial.length === 0
					? "{}"
					: gap
						? "{\n" + gap + partial.join(",\n" + gap) + "\n" + mind + "}"
						: "{" + partial.join(",") + "}";
			gap = mind;
			return v;
	}
}

// If the JSON object does not yet have a stringify method, give it one.

meta = {
	// table of character substitutions
	"\b": "\\b",
	"\t": "\\t",
	"\n": "\\n",
	"\f": "\\f",
	"\r": "\\r",
	'"': '\\"',
	"\\": "\\\\"
};

module.exports = function (value, replacer, space) {
	// The stringify method takes a value and an optional replacer, and an optional
	// space parameter, and returns a JSON text. The replacer can be a function
	// that can replace values, or an array of strings that will select the keys.
	// A default replacer method can be provided. Use of the space parameter can
	// produce text that is more easily readable.

	var i;
	gap = "";
	indent = "";

	// If the space parameter is a number, make an indent string containing that
	// many spaces.

	if (typeof space === "number") {
		for (i = 0; i < space; i += 1) {
			indent += " ";
		}

		// If the space parameter is a string, it will be used as the indent string.
	} else if (typeof space === "string") {
		indent = space;
	}

	// If there is a replacer, it must be a function or an array.
	// Otherwise, throw an error.

	rep = replacer;
	if (
		replacer &&
		typeof replacer !== "function" &&
		(typeof replacer !== "object" || typeof replacer.length !== "number")
	) {
		throw new Error("JSON.stringify");
	}

	// Make a fake root object containing our value under the key of "".
	// Return the result of stringifying the value.

	return str("", { "": value });
};
